Footwear, such as shoes, nearly all include a sole for support that may be made of rubber, foam, or some other material. While offering support and comfort to people's feet, soles themselves are usually somewhat rigid for various reasons. For one, the sole must support a person's foot when walking and running across different surfaces that are not always even. Hiking, for example, challenges people to move across uneven wilderness that can require a person to climb hills, scale rocks, or otherwise move across uneven surfaces, none of which present perfectly flat surfaces for the sole of a shoe to land. Even activities as simple are running or walking often present terrain that is uneven, inclined, or declined in some manner. When a foot hits nonlevel surfaces, different areas of the foot absorb more force than others. So shoe soles must be flexible enough to fit feet contorting in different ways on nonlevel surfaces.